The physicochemical and microbiological dynamics during the fermentation phase of the CCN51 cocoa material was evaluated in three maturity stages (stage 2: 130-152 days after anthesis (DAA), stage 3: 153-174 DAA, and stage 4: 175-196 DAA). Through the microfermentation technique, the physicochemical variables (pH, titratable acidity, total soluble solids, and fermentation index) were monitored every 24 hours. The microbiological dynamics were evaluated by counting the colony forming units (CFU) in a plaque, quantifying three types of microorganisms (Bacillus, acetic acid bacteria and yeasts). In the three maturity stages assessed, a decrease in the pH of the beans was observed as the fermentation progressed; between 72 and 96 hours after fermentation, the pH of stage 4 beans was different from stages 2 and 3. Simultaneously, an increase in the pH of the pulp was observed without differences between the stages. Brix degrees did not show statistical differences between stages, however, the values of total soluble solids showed that the microorganisms present in stage 3 were more effective in metabolizing these in comparison with those of stages 2 and 4. Regarding the fermentation index, stage 4 reached the maximum value (1.35 ± 0.16) at 120 hours, meanwhile stages 2 and 3 reached it at the end of the fermentation (1.35 ± 0.01 and 1.55 ± 0.29, respectively) at 168 hours. The microbiological dynamics in the three cocoa fruit maturity stages evidenced the absence of lactic acid bacteria and the presence of mesophilic aerobic bacilli. Yeasts were present throughout the fermentation in the three maturity stages, being more favored by stage 2, meanwhile, acetic acid bacteria were favored by stage 3. Outstanding microorganism species were characterized molecularly as Pichia kudriavzevii,Bacillus subtilisBacillus megaterium, and Bacillus tequilensis. Stage 3 showed the best characteristics to obtain good quality cocoa.

Las características de los productos agrícolas están influenciadas por el ecosistema desde la perspectiva de los factores bióticos y abióticos, lo cuales producen en la planta respuestas fisiológicas y a su vez en los frutos propiedades fisicoquímicas únicas, que son la base para las denominaciones de origen y estrategias de agregación de valor al producto en el mercado actual. En el presente trabajo se caracterizaron morfoagronómicamente diez materiales de cacao (Theobroma cacao L.) que fueron seleccionados por su destacada productividad (FSV41, FLE3, FEAR5, FSA12, FEC2, SCC23, SCC80, SCC55, ICS95 y CCN51), los cuales fueron establecidos en departamentos como Santander (931 m s. n. m.), Huila (885 m s. n. m.) y Arauca (204 m s. n. m.), principales zonas productoras de cacao en Colombia. Para la evaluación de las características físicas de materiales recolectados se utilizaron 21 descriptores cuantitativos encargados de definir la variabilidad física del fruto según el clon y el lugar donde se recolecto. Los datos recolectados fueron analizados mediante la matriz de correlación de Pearson y análisis de componentes principales, logrando identificar aquellos descriptores que más aportan a la variabilidad entre materiales (índice de mazorca, relación longitud diámetro, peso y diámetro de semilla y peso y longitud de fruto). Además, se pudo comprobar el efecto del lugar de cosecha sobre las características físicas de los materiales resaltando la importancia del estudio de adaptación previo a la siembra del material de cacao, con el objetivo de garantizar una cosecha de cacao Premium, productiva y de calidad para la industria, que compita en el mercado.

Cocoa fermentation process is fundamental to generate flavors and aromas that are characteristics of chocolate. In Colombia, this process is carried out by microbiota that spontaneously colonizes cocoa beans, therefore the quality of the fermentation is inconsistent. Taking into account that the fermentation of cocoa beans is carried out by a consortium of microorganisms, the aim of thisresearch was to describe the effect of the addition of a specific mixture of yeasts, acetic acid bacteria, and lactic acid bacteria on the physicochemical and organolepticcharacteristics of cocoa beans (clone CCN 51). Isolates of two yeasts (Wickerhamomyces anomalus and Debaryomyces hansenii), three acetic acid bacteria (AAB), (Gluconobacter japonicus, Acetobacter tropicalis, and Acetobacter pasteurianus) and three lactic acid bacteria (LAB) (Pediococcus acidilactici, Lactobacillus brevis, and Lactobacillus plantarum) obtained fromprevious cocoa fermentations selected for their pectinases and acid production capacities in a specific mixture were used. Using the micro-fermentation technique, the effect of a biological starter was evaluated under different viable microorganismsratios (Yeasts: LAB: AAB as follows, 1: 1: 1, 1: 2: 2, 1: 2: 1, 1: 1: 2, 2: 1: 1, 2: 2: 1, 2: 1: 2, and 2: 2: 2). The concentration of each microorganism was standardized at 1x107 cfu/mL, then the biomass of 4 mL for ratio 1 and 8 mL for ratio 2 of each suspension of microorganisms was added at time zero. Different doses of inoculum were 0%, 1%, 2%, 3%, 4%, and 5% v/w mL inoculum/g cocoa beans. A beneficial effecton the sensory quality of cocoa beans was evidenced by the addition of microorganisms; the best proportion of microorganisms was 2:1:2 (yeasts:LAB:AAB) and the best inoculum dose was 3% (v/w) showing lower acidity, astringency, and bitterness, and emphasizing the cocoa flavors, fruity, nutty, and panela malt.

BACKGROUND: Microencapsulated yeasts are a novel alternative as a delivery matrix for microbiological starters. This technology aims to protect the active compounds from adverse environmental conditions and prolong their useful life and could also improve the conditions of the starters for cocoa fermentation. The present study established the effective dose to apply the microencapsulated yeast Pichia kudriavzevii as a microbiological starter of fermentation and biotechnological strategy for promoting the biochemical dynamics and sensory expression of the cocoa variety CCN-51. For this, 0.5%, 1%, 2%, and 3% of microencapsulated P. kudriavzevii yeast insolated from the artisanal fermentation process of cocoa was added to the cocoa mass to be fermented and studied on a laboratory scale. RESULTS:The partial least squares regression of fermentation was related in four quartiles, comprising the hedonic judgments of the sensory evaluation with the biochemical traits of the cocoa liquor, finding a high correlation between the physicochemical variables total phenols, percentage of insufficiently fermented grains, and percentage of total acidity, with a level of bitterness and defects found in liquors with the addition of 0.5% of microencapsulated starter. The treatments with the addition of 2% and 3% of the inoculum showed a high correlation between the variables pH, total anthocyanins, cocoa, fruity and floral aromas, sweet taste, and general aroma perception. CONCLUSION: The higher presence of volatile compounds such as 2,3-butanediol associated with cocoa aroma and 1-phenyl-2-ethanol and acetophenone associated with aromatic descriptors of fruity and floral series allowed establishment in 2% of microencapsulated P. kudriavzevii yeast, comprising the effective dose for promoting the biochemical dynamics of laboratory-scale fermentation and the development of cocoa, as well as the fruity and floral aromas of cocoa CCN-51 liquor. The microencapsulation is suitable for cocoa starters.